diff --git a/src/serialization.cpp b/src/serialization.cpp
index 1fd75c97a..118bad467 100644
--- a/src/serialization.cpp
+++ b/src/serialization.cpp
@@ -20,7 +20,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "serialization.h"
 
 #include "util/serialize.h"
-#ifdef _MSC_VER
+#ifdef _WIN32
 	#define ZLIB_WINAPI
 #endif
 #include "zlib.h"